Transmission electron microscope provided with at least one ballistic material jet source

Patent metadata

Field	Value
Publication number	US-11239049-B2
Application number	US-201917049866-A
Country	US
Kind code	B2
Filing date	Apr 30, 2019
Priority date	May 2, 2018
Publication date	Feb 1, 2022
Grant date	Feb 1, 2022

Abstract

A transmission electron microscope is provided, including a column defining an object chamber, at least one ballistic material jet source outside the object chamber, and tightly attached to the column, facing an opening, referred to as a port, provided on the column; having at least one jet source arranged outside the column and including a collimator of the material jet towards a predetermined direction, passing through the port and leading into the object chamber so that a portion of the material jet exits the source in the object chamber.

First claim

The invention claimed is:

1. A transmission electron microscope, comprising:
a column delimiting an object chamber;
at least one ballistic material jet source:
outside said object chamber;
fixed in a sealed manner to said column, facing an opening, called a port, provided on said column; and

at least one jet source is arranged outside the column and comprises a collimator of the material jet towards a predetermined direction, said collimator passing through the port and leading into the object chamber so that a portion of the material jet exits said source in said object chamber.

2. The microscope according to claim 1 , characterized in that the collimator is arranged to trap particles of the material jet which are not emitted in the predetermined direction and to prevent these particles that were not emitted in the predetermined direction from passing into the object chamber.

3. The microscope according to claim 1 , characterized in that at least one source comprises any combination of one or more material jet generators selected from:
an effusion cell,
a plasma source,
a radical generator using thermal cracking, and
an electron bombardment evaporator.

4. The microscope according to claim 3 , characterized in that at least one source comprises at least one material jet generator that can be removed through an opening provided on said source.

5. The microscope according claim 1 , characterized in that the collimator has a cross section which decreases in the direction of the material jet.

6. The microscope according to claim 1 , characterized in that at least one source comprises at least one shutter for interrupting the material jet towards the object chamber.

7. The microscope according to claim 1 , characterized in that at least one source comprises at least one heat shield arranged around a material jet generator.

8. The microscope according claim 1 , characterized in that at least one source comprises a pump opening for connection thereto of a pump device adjusting, and in particular lowering, the pressure inside said source.

9. The microscope according to claim 1 , characterized in that it comprises, for at least one source, an adjustment means, called aiming adjustment means, for adjusting the direction of the material jet, in at least one spatial direction.

10. The microscope according to claim 9 , characterized in that, for at least one source, the aiming adjustment means comprises:
a bellows arranged between said source and the column of said microscope; and
at least one means for modifying the compression of said bellows following at least one point, in particular in the form of a screw.

11. The microscope according to claim 10 , characterized in that, for at least one source, the aiming adjustment means comprises at least one means for modifying the position of the material jet collimator within said source.

12. The microscope according to claim 1 , characterized in that, for at least one source the inside of said source communicates with the object chamber only though the material jet collimator.

13. The microscope according to claim 1 , characterized in that at least one source comprises:
a ballistic material jet generator, such as an effusion cell;
two concentric heat shields around said generator;
a material jet collimator downstream of said generator;
a shutter between said generator and said collimator; and
a means for adjusting the aiming direction.

14. The microscope according to claim 1 , characterized in that it comprises means for maintaining the collimator at a temperature that is low enough that the particles from the material jet emitted upstream and in the direction of the walls of the collimator are trapped there, this low enough temperature preferably being lower than 25° C.

Assignees

• Centre Nat Rech Scient

Inventors

• Harmand Jean-Christophe
• Travers Laurent
• Ollivier Yannick

Classifications

• H01J37/26 Primary

  Electron or ion microscopes; Electron or ion diffraction tubes · CPC title

• H01J2237/2067

  Surface alteration · CPC title

• H01J2237/2002

  Controlling environment of sample · CPC title